Which version of iOS 12.1.2 is correct? I'm puzzled...

I recently updated my iPhone X to iOS 12.1.2 via WiFi. No problems, everything is working fine. Yesterday I connected my phone to my iMac (macOS Mojave 10.14.2, iTunes 12.9.2) in order to do a backup via iTunes, which promptly informed me that a new version of iOS 12.1.2 was available. I ignored this, as I wasn't sure what to do!

I´m aware that a slightly newer version of iOS 12.1.2 appeared almost immediately after the initial release, with a build version ending in 104, I believe. The version on my iPhone is 12.1.2 (16C101).

Obviously iTunes sees my iOS as requiring an update, but I´m not sure whether to do this or just ignore iTune´s promptings! Any suggestions/help? Thanks in advance! Regards, Ian.